The present invention relates to an interconnection-type vehicle body structure, particularly for a motor vehicle, having at least one interconnecting element that connects profiled frame parts to one another.
Body structures for motor vehicles are known which are made of an aluminum material and in which extruded sections are mutually connected by way of interconnecting elements consisting of die-castings. In addition, it is known in the case of a vehicle body structure to construct interconnecting parts and profiled parts connected thereto in a composite design, i.e. by means of elements consisting of different materials. For example, it is suggested in German Patent Document DE 19808392 A1 to mutually connect plastic profiles by use of cast light-metal interconnecting parts. Likewise, it is described in German Patent document DE 102010013344 A1 to construct a body shell, among others, by use of a supporting frame, that has so-called interconnecting devices, which are made of cast aluminum and connect profiles made of fiber-reinforced plastic material with one another. Known vehicle body structures are especially constructed with the goal of sufficient rigidity for a normal operation of a motor vehicle and with respect to occupant safety in the event of a collision.
It is an object of the present invention to provide an interconnection-type vehicle body structure that is light, can be produced more cost-effectively and nevertheless meets the demands on the vehicle body structure in the case of a collision load.
This and other objects are achieved by an interconnection-type vehicle body structure, particularly of a motor vehicle, having at least two profiled frame parts made of a fiber-reinforced composite material and an interconnecting element which mutually connects the profiled frame parts. The interconnecting element has receptacles for the profiled frame parts and is constructed of at least two sheet metal shells.
An interconnection-type vehicle body structure according to the present invention has at least two profiled frame parts made of a fiber-reinforced composite material and an interconnecting element which mutually connects the profiled frame parts. The interconnecting element has receptacles for the profiled frame parts. It is constructed of at least two sheet metal shells. The interconnecting element is therefore neither produced of a cast metal nor of a fiber-reinforced plastic material.
Sheet metal shells can be produced in a particularly cost-effective manner in large quantities. Especially in comparison with cast parts, sheet metal shells are more cost-effective, at least for simpler geometries. Because the interconnecting element is constructed of at least two parts, very stable three-dimensional interconnecting elements can be produced in the sheet metal shell construction. Likewise, the profiled frame parts can be produced comparatively cost-effectively from a fiber-reinforced plastic composite. This construction is also advantageous because the profiled frame parts made of fiber-reinforced composite material have the tendency to fail in a brittle manner after a slight elastic deformation, whereas interconnecting elements in a shell construction and of a metallic material can plastically deform in the case of overstraining. Despite the construction with profiled frame parts made of fiber-reinforced composite material, as a whole, this permits a greater plastic deformability of the vehicle body structure compared to a vehicle body structure whose interconnecting elements are also produced of fiber-reinforced composite material. Relative to weight, the vehicle body structure according to the invention has high rigidity for a normal operation of the vehicle body structure as well as high strength in the event of a collision load, in which case, by use of the interconnecting element made of at least two sheet metal shells, the probability of an occurrence of a sudden failure of the vehicle body structure and, particularly, of the profiled frame parts is reduced, for example, when they are strained by bending in the event of a collision load.
Sheet metal shells are especially three-dimensional elements which are produced, for example, by cold and/or warm forming of semi-finished sheet metal products.
The vehicle body structure, for example, is the vehicle body structure of a motor vehicle, particularly of a passenger car, which has to meet specific requirements in the event of a collision of the motor vehicle for protecting occupants of the motor vehicle.
In particular, a fiber-reinforced composite material is a plastic material reinforced by fibers. In other words, the fiber-reinforced composite material has a matrix made of plastic material, in which fibers are integrated for improving the strength characteristics of the plastic material.
The profiled frame part may be constructed of continuous fibers. The continuous fibers may previously have been prepared for forming a semi-finished fiber product by use of a braiding process or a winding process or by another method. In this case, the use of tri-axially braided continuous fibers is preferred. The fibers may be carbon fibers or other suitable fibers. The plastic matrix may be a duroplastic material, such as epoxide, as well as a thermoplastic material.
Naturally, an interconnection-type vehicle body structure may be constructed of a multiplicity of profiled frame parts and interconnecting element connecting the latter. In this case, all interacting elements and profiled frame parts can appropriately interact with respect to the stiffness and strength of the vehicle body structure.
Interconnecting elements may also be constructed of more than two sheet metal shells, which is advantageous, for example, in the case of a complex geometry that cannot be configured by use of two sheet metal shells.
According to a preferred further development, the interconnecting element is constructed such that, in the event of a collision of a motor vehicle having the vehicle body structure, it can be plastically deformed at a predetermined force.
The sheet metal shells advantageously each have a connecting flange by which the two sheet metal shells are mutually connected. In the case of more than two sheet metal shells of the interconnecting element, advantageously all sheet metal shells are mutually connected by flanges.
Connecting flanges permit a particularly simple connection of the sheet metal shells.
The sheet metal shells are preferably connected with one another in a frictional, interlocking and/or firmly bonded manner. Examples of such connections are welded connections, glued connections and bolted connections—screws or rivets—, which can also be arbitrarily combined with one another.
In particular, these connections are well suited for the connection of connection-forming flanges.
The connection of sheet metal shells can also easily be implemented in an automated manner.
According to a further development of the present invention, the profiled frame parts may be connected in a frictional, interlocking and/or firmly bonded manner, particularly by gluing and/or by a bolted connection with the pertaining receptacle of the interconnecting element.
According to an additional further development, one profiled frame part or both profiled frame parts may have a closed hollow profile; i.e. a cross-section of the hollow profile is closed transversely to its longitudinal dimension.
A closed hollow profile is advantageous with respect to bending stress in all directions of the profiled frame part and is therefore more stable with respect to an open profiled cross-section.
At least one receptacle is preferably designed such that it reaches around or encompasses an outer circumference of the pertaining profiled frame part; an outer circumference of a fastening section of the profiled frame part is preferably completely surrounded by the receptacle. The profiled frame part is therefore advantageously inserted with its fastening section into the receptacle.
Conversely, at least one receptacle may be designed such that it has a protrusion which the pertaining profiled frame part encompasses. In this case, this fits the profiled frame parts with its fastening section preferably onto the receptacle.
According to a further development, the profiled frame parts are vehicle body elements of a vehicle occupant compartment. A profiled frame part may preferably be a roof frame element or a roof side frame element. Furthermore, a profiled frame part may be a vehicle body pillar element. In addition, a profiled frame part may be a transverse roof bow element. Furthermore, a profiled roof part may be a side sill element. In addition or as an alternative, a profiled frame part may be a transverse floor bow element.
The entire vehicle occupant compartment or sections of the vehicle occupant compartment may be constructed of the vehicle body structure according to the invention.
According to a preferred embodiment, the interconnecting element connects three or four profiled frame parts with one another. The interconnecting element may, for example, mutually connect a roof pillar element, particularly a B-pillar, a roof frame or roof side frame and a transverse roof bow element.
The sheet metal shells are advantageously made of steel plates.
Steel plates can be formed particularly easily and cost-effectively and have an advantageous capability of plastically deforming and therefore have a certain ductility.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.